A large part of your income, especially in a small realm, comes from the personal holdings of your demesne.
Holding Income = (Base Income + Building Income) x (1 + Local Income Modifiers) x (1 + Owner Income Modifiers)
The Base Holding Income is the sum of:
- the Base Income of the holding: 0.5 for a tribe, 4 for a castle, 8 for a temple, or 12 for a city.
- the Building Income brought by all buildings constructed in the holding
Local Income Modifiers include province and holding modifiers. They include:
- Technology boost from "Castle Infrastructure" tech (up to +50%) and "Cities and Temples" tech (up to 40%).
- Muslim Infidel tax on non-Muslim provinces: +25%
- Steward's Collect Taxes job, which depends on Steward's stewardship attribute: +2.5% tax/skill point. Note that it only applies to holdings owned by the Steward's liege, so they are best used in counties where the liege owns more than one holding.
- Wrong government type penalty of -75%, in case the owner's government type does not match the holding type.
- Looted province penalty, if a province has been raided or hostile armies lived off loot for supply
- New administration penalty of -30%
- Recently conquered penalty of -100%
- Prosperity
Owner Income Modifiers include:
- State stewardship, +2% per point
- For Muslims, decadence above 25% decreases demesne income, while decadence below 25% increases it.
- Modifiers confusingly called "National Tax Modifier", such as:
(+10%)- Expelled Jews (-10%)
- A penalty of -25% per holding above the demesne limit, with a maximum of -90%.
| Exceeding Demesne limit | By 1 | By 2 | By 3 | By 4 and above |
| Income penalty | -25% | -50% | -75% | -90% |